1. Field of the Invention
The present invention relates to a positioning apparatus for positioning a plate-like object such as a piezoelectric element to a target position corresponding to, for example, an attaching part of a head suspension to which the plate-like object is attached.
2. Description of Related Art
Japanese Unexamined Patent Application Publication No. 2002-050140 discloses a plate-like piezoelectric element to be attached to a dual-actuator-type head suspension that is installed in a hard disk drive.
Attached to the head suspension, the piezoelectric element works to minutely move a magnetic head arranged at a front end of the head suspension so that the magnetic head is precisely positioned to a target location on a hard disk of the hard disk drive. With the piezoelectric element, the head suspension realizes an improved magnetic head positioning accuracy to handle even a very-high-density hard disk.
To realize a required magnetic head positioning accuracy, the piezoelectric element must precisely be attached to the head suspension. If the piezoelectric element on the head suspension involves a positioning error, the magnetic head of the head suspension will cause a stroke error. The piezoelectric element, therefore, must correctly be positioned and fixed to a piezoelectric element attaching part of the head suspension.
For this, the piezoelectric element is positioned to a target position that corresponds to the attaching part of the head suspension and is attached to the attaching part with the positioned state of the piezoelectric element being maintained.
A technique of positioning an object to a target position is disclosed in Japanese Unexamined Patent Application Publication No. 2008-112901. This related art is a positioning apparatus having a pushing plate and a reference plate. The related art pushes a piezoelectric element with the pushing plate to the reference plate so that the piezoelectric element is positioned to a target position and clamps the piezoelectric element at the target position.
At this time, the piezoelectric element will crack or chip if it involves shape variations and if it is tightly clamped between the pushing plate and the reference plate.
To avoid this, the related art must loosely clamp the piezoelectric element at the target position. This, however, results in losing positioning accuracy and reliability of the positioned piezoelectric element.
In addition, even if the clamping force is reduced, it is unable to eliminate a risk of damaging the piezoelectric element.